A user terminal like a mobile phone, a tablet computer or a personal digital assistant (PDA) may have a plurality of audio capturing elements such as multiple microphones. Such configuration has become popular in past several years. For example, those commercially available smart mobile phones are usually equipped with two or more microphones. Generally speaking, among the plurality of audio capturing elements on a single user terminal, some of them are designed to function as primary audio capturing elements and used to capture, for example, the foreground audio signals; while the audio capturing elements may function as reference or auxiliary ones and used to capture, for example, the background audio signals. As an example, a microphone located in the lower part of a mobile phone is generally supposed to be capable of capturing high quality of voice signals from a speaker. Therefore, this microphone is usually used as a primary audio capturing element to capture the user's speech signal in a voice call. A microphone at another location may function as an auxiliary audio capturing element that may be used to capture the background noise for environmental noise estimation, noise inhibition, and the like.
Those skilled in the art would appreciate that the spatial location of a user terminal with respect to the audio signal source and the surrounding environment will have an impact on the effects of audio capturing. For example, in some situations, the originally designed primary audio capturing element might be blocked or located opposite to the audio signal source of the user terminal, thereby rendering the originally designed primary audio capturing element incapable of capturing audio signals of high quality. However, in the prior art, an auxiliary or reference audio capturing element cannot be activated to function as a primary one in this situation, even if this element is now in a better or optimal position. In other words, the functionalities of audio capturing elements on the user terminal are fixed in design and manufacturing, and cannot be changed or switched adaptively in use. As a result, the quality of audio capturing will degrade.
In view of the foregoing, there is a need in the art for an audio capturing solution that may be adaptive to various conditions in use.